Coxiella burnetii (Q fever)


Coxiella burnetii 

  • Characteristics
    • Gram negative coccobacilli
    • obligate intracellular
  • Transmission
    • Inhalation of aerosolized spores
    • Seen in occupational exposures to farm animals
      • From placental or amniotic fluid of livestock
      • Humans are incidental hosts (not natural carriers)
  • Presentation: Q fever
    • Flu-like symptoms (fever, headache)
    • mild pneumonia
    • hepatitis
      • Elevated ALT and AST
    • May cause culture-negative endocarditis
  • Diagnosis
    • Usually clinical; although may be supplemented with testing
    • Blood cultures usually negative
    • Immunofluorescence assay for IgG against Coxiella is used to confirm diagnosis
  • Treatment
    • Doxycycline is first-line
      • TMP-SMX given if doxycycline is not tolerated
      • Hydroxychloroquine may be added with cardiac involvement